public class Demo16 {
    private static int count = 0;
    private static int count2 = 0;

    public static void main(String[] args) throws InterruptedException {
        Object locker = new Object();
         Thread t1 = new Thread(() -> {

             for (int i = 0; i < 50000; i++) {
                 synchronized (locker) {
                     count++;
                 }
             }
         });

         Thread t2 = new Thread(() -> {
             for (int i = 0; i < 50000; i++) {
                 synchronized (locker) {
                     count++;
                 }
             }
         });

         t1.start();
         t2.start();
         t1.join();
         t2.join();

        System.out.println(count);
    }
}
